Ken Livingstone saw his odds of becoming next London Mayor actually decrease to 6-4 on Betfair on the day that he officially launched his campaign for re-election.

Livingstone – who started the day at 7-5 – was clearly trying to refocus the attention on the issues in light of the character assaults and scandals that have surrounded the Mayor and his office in recent weeks.  The YouGov poll published yesterday showed the Labour man having some way to go if he is to be successful in extending his stay at the helm beyond the eight years he has already had.

Conservative challenger Boris Johnson remains the 4-6 favourite on Betfair, while at 54-1 the Lib Dem candidate, Brian Paddick, is given little chance.

Betfair’s Mike Robb said, “Although the opening of nominations today officially marks the start of the election, campaigning has been going on for months now and Ken’s media launch has had a slightly negative impact on the Betfair market.  Interest in this election is likely to pick up considerably now that there is a break in the US Primary schedule and it will be interesting to watch Betfair customers react to events in London over the next six weeks.”

To be the next Mayor of London – Betfair bet: 4-6 Boris Johnson, 6-4 Ken Livingstone, 54-1 Brian Paddick, 179-1 Any Other